This invention relates to an ion beam apparatus for irradiating a specimen with an ion beam thereby effecting processing such as cutting a groove, etc. in the surface of the specimen by utilizing the ion beam, and analysis on the specimen, and more particularly to an ion beam apparatus suitable for microprocessing and microanalysis of such specimens as semiconductor wafers.
In the conventional apparatus for effecting microprocessing and microanalysis on a given specimen by the use of an ion microbeam as described in Japanese Patent Application Laid-open No. SHO 52(1977)-142,580, the specimen under treatment is kept at a temperature below the melting point of the raw material for the aforementioned ion beam. When the ion beam generated with a metallic element or compound is projected on the given specimen in a cumulative amount exceeding a certain level under the condition described above, the primary ion species adheres unevenly on the surface of the specimen and moves around on the surface. This phenomenon entails the following problems.
(1) The deposit on the rear surface of the specimen plays the part of a mask during the processing and analysis and brings about a critical adverse effect upon the two operations.
(2) The deposit causes pollution of the specimen and induces degradation of the properties of the production of processing.